C. cassia oil at the concentration of 0.01875% (v/v) inhibited the growth of O26:H11 and O145:NT for up to 24 hours, and increased the duration of lag phase of O45:NM, O103:H2, O111:H2, O121:H19 by 18, 12, six, and 16 hours, respectively.

At the high inoculation population (∼5 × 106 CFU/mL), C. cassia oil was less effective, said the researchers.

C. cassia oil at 0.00625% or 0.0125% (v/v) had limited efficacy in inhibiting the growth of all test non-O157 STECs.

Including 0.01875% (v/v) C. cassia oil delayed the log phase of O45:NM, O103:H2, O111:H2, and O121:H19 for about three hours, and O26:H11, O145:NT for eight and 10 hours, respectively.

Including 0.01875% (v/v) it decreased the stationary phase population of O26:H11, O45:NM, O103:H2, and O121:H19.

C. cassia oil at 0.025% (v/v) inhibited the growth of O121:H19 and O145:NT for at least 24 hours and elongated the duration of lag phase of O45:NM, O103:H2, and O111:H2 for less than eight hours and O26:H11 for less than 14 hours.

The US Department of Agriculture Food Safety and Inspection Service has a “zero tolerance” policy for the Centers for Disease Control and Prevention (CDC) top six non-O157 STECs in raw ground beef and trimmings, so any raw non-intact beef products containing these pathogens are adulterated.